/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 页面基础样式 */
html, body {
    height: 100%;
    font-family: 'Arial', sans-serif;
}

body {
    display: flex;
    justify-content: center;
    align-items: center;
    background: url('../images/background.jpg') no-repeat center center fixed;
    background-size: cover;
    position: relative;
}

/* 半透明覆盖层 */
body::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: -1;
}

/* 登录容器样式 */
.login-container {
    width: 100%;
    max-width: 600px;
    padding: 40px;
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    animation: fadeIn 0.5s ease-in-out;
}

.login-container h2 {
    text-align: center;
    margin-bottom: 30px;
    color: #333;
    font-size: 24px;
}

/* 表单样式 */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #555;
}

.form-group input {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.form-group input:focus {
    border-color: #4CAF50;
    outline: none;
}

/* 按钮样式 */
.btn-login {
    width: 100%;
    padding: 12px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s;
    margin-top: 10px;
}

.btn-login:hover {
    background-color: #45a049;
}

/* 错误消息样式 */
.error-message {
    color: #e74c3c;
    text-align: center;
    margin-bottom: 20px;
    padding: 10px;
    background-color: rgba(231, 76, 60, 0.1);
    border-radius: 5px;
}

/* 动画效果 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式调整 */
@media (max-width: 480px) {
    .login-container {
        padding: 30px 20px;
        margin: 0 15px;
    }
}